Question

I’m generating a reporting services report from an ASP.NET (MVC) based application but am having problems setting the parameters for the report.

I believe the issue has only occurred since we upgraded SQL Server from 2005 to 2008 R2 (and Reporting Services along with it).

The original error encountered was from calling rsExec.Render:

Procedure or function ‘pCommunication_ReturnRegistrationLetterDetails’
expects parameter ‘@guid’, which was not supplied.

Debugging the code I noticed that rsExec.SetExecutionParameters is returning the following response:

Cannot call ‘NameOfApp.SQLRSExec.ReportExecutionService.SetExecutionParameters(NameOfApp.SQLRSExec.ParameterValue[],
string)’ because it is a web method.

Here is the function in it’s entirety:

public static bool ProduceReportToFile(string reportname, string filename, string[,] reportparams, 
    string fileformat)
{
    bool successful = false;
    SQLRS.ReportingService2005 rs = new SQLRS.ReportingService2005();
    SQLRSExec.ReportExecutionService rsExec = new NameOfApp.SQLRSExec.ReportExecutionService();

    rs.Credentials = System.Net.CredentialCache.DefaultCredentials;
    rsExec.Credentials = System.Net.CredentialCache.DefaultCredentials;

    // Prepare Render arguments
    string historyID = null;
    string deviceInfo = null;

    // Prepare format - available options are "PDF","Word","CSV","TIFF","XML","EXCEL" 
    string format = fileformat;

    Byte[] results;
    string encoding = String.Empty;
    string mimeType = String.Empty;
    string extension = String.Empty;

    SQLRSExec.Warning[] warnings = null;
    string[] streamIDs = null;

    // Define variables needed for GetParameters() method
    // Get the report name
    string _reportName = reportname;
    string _historyID = null;
    bool _forRendering = false;
    SQLRS.ParameterValue[] _values = null;
    SQLRS.DataSourceCredentials[] _credentials = null;
    SQLRS.ReportParameter[] _parameters = null;

    // Get if any parameters needed.
    _parameters = rs.GetReportParameters(_reportName, _historyID,
                    _forRendering, _values, _credentials);

    // Load the selected report.
    SQLRSExec.ExecutionInfo ei =
            rsExec.LoadReport(_reportName, historyID);

    // Prepare report parameter.
    // Set the parameters for the report needed.
    SQLRSExec.ParameterValue[] parameters =
            new SQLRSExec.ParameterValue[1];

    // Place to include the parameter.
    if (_parameters.Length > 0)
    {
        for (int i = 0; i < _parameters.Length; i++)
        {
            parameters[i] = new SQLRSExec.ParameterValue();
            parameters[i].Label = reportparams[i,0];
            parameters[i].Name = reportparams[i, 0];
            parameters[i].Value = reportparams[i, 1];
        }
    }
    rsExec.SetExecutionParameters(parameters, "en-us");
    results = rsExec.Render(format, deviceInfo,
                out extension, out encoding,
                out mimeType, out warnings, out streamIDs);

    // Create a file stream and write the report to it
    using (FileStream stream = System.IO.File.OpenWrite(filename))
    {
        stream.Write(results, 0, results.Length);
    }
    successful = true;

    return successful;
}

Any ideas why I’m now unable to set parameters? The report generation works without issue if parameters aren’t required.

Answer 1

Looks like it may have been an issue with how reporting services passes parameters through to the stored procedure providing the data. A string guid was being passed through to the report and the stored procedure expected a varchar guid. I suspect reporting services may have been noticing the string followed the guid format pattern and so passed it through as a uniqueidentifier to the stored procedure.

I changed the data source for the report from “stored procedure” to “text” and set the SQL as “EXEC pMyStoredOProcName @guid”.

Please note the guid being passed in as a string to the stored procedure is probably not best practice… I was simply debugging an issue with another developers code.